Mercurial
by Dragon'sHost
Summary: Pretending to be a good guy is tough. But mercury in its common form is a fluid element that changes shape to fit its environment.
**So here's my first ever attempt at an RWBY fic. And I choose to make it about the single most difficult character to write about that I've ever encountered.**

 **This fic is going to be Mercury-centric, and mostly revolve around canon events. I have no plans for any ships at the moment. Mostly because I have no idea what half the ship names even are.**

 **Disclaimer: I do not own RWBY.**

* * *

 ** _Prologue_**

* * *

Mercury Black was many things.

He knew he wasn't a good person, though. It didn't matter what metric was used, or how far a stretch of imagination. Oh there were excuses, of course. Reasons, maybe. Explanations.

Absently, Mercury rubbed his right leg, at the place where skin met metal, where false limb connected to the real one (or what was left of it, anyway). Sometimes it hurt. Mostly it itched. Making the switch from long pants to shorts had been the right move, he decided, digging his fingertips into his skin to relieve the irritating sensation. Even if the borrowed shorts were a horrendous shade of orange no normal human would ever consider donning. Reaching the itchy parts was a lot harder in his old attire, though. Much easier to access like this.

Far more difficult to alieve was the itch to get up and _do_ something with himself. The teenager's skin positively crawled with the need to move around, to kick something.

Outside the room's window, leaves silently drifted to the ground. It wouldn't be long until it was snow falling there instead, Mercury mused. Maybe he could go outside and… chop firewood or something. Anything was better than staying in this stifling room, in this stupid, wooden chair that no matter how he situated himself in it, he just couldn't seem to find a comfortable postion. Seriously, was the thing made specifically to torture its occupants? That would explain a lot.

Mercury pulled out his scroll, checking the time. Ten more minutes until he was relieved of this chore, and could move onto something else. At least for the next couple of hours. Maybe he could call Emerald and pester her… oh, right. Communications were spotty right now, and Emerald was all the way in Atlas. With the Tower down… well, there was no way to reach her right now. That was assuming she even had her scroll with her still.

"Getting antsy already?"

Stiffening, Mercury cast a wary glance over his shoulder at the intruder leaning against the doorframe. "Just watching someone sleep is boring. At least let me draw on her face or something."

A snort came from the older man. "Tai would pitch a fit."

"Only because he didn't come up with it first."

Qrow opened his mouth to object, paused, and then closed it again. He shook his head and groaned. "Speaking of, he's attempting to make food. Stop him, please."

Standing up from the chair, Mercury stretched out his arms. "His food's edible." Much better than anything Emerald ever tried to make, anyway. And Cinder's name was Cinder for a reason.

The Hunter regarded him for a long moment, his eyes narrowed. "I have to wonder what sort of food you grew up on."

"Stolen," Mercury replied, lowering his arms. "I'll leave Red to you then. I need to go kick in some Grimm teeth or I'll go batty."

Qrow didn't budge from the doorway. "So I picked up the White Fang's trail in Haven," he said, almost conversationally.

"That's fantastic, can I leave now?"

"Hold on, hold on." Appraising him, Qrow observed aloud, "You're awfully tense today. Have somewhere you need to be?"

"Nope. You just smell bad." Indeed, the smell coming off the Hunter was beginning to fill up the room, making Mercury's head spin. He needed to get out of there. He was going to kill something, and he didn't think Ruby or Yang would appreciate that something being their beloved uncle.

Surprised, Qrow lifted his arm and sniffed. "…You're not wrong," he conceded. Stepping aside, he waited for Mercury to pass by. Just as he was almost out in the corridor, Qrow stated, "You know, it's odd. That you knew exactly where the White Fang would be heading."

With a roll of his eyes, Mercury didn't stop. "It was a lucky guess."

Qrow watched the boy leave in silence. Once he heard the outside cabin door open and slam close, he sighed. "Something about that kid… I don't like him. Something's off about him."

The fluffy, yellow head of his old teammate popped out of another doorway. "Mercury?"

"Yeah. I'm sure you've noticed it, too."

Taiyang considered it. "He doesn't seem like he cares about much but…" He glanced down the empty corridor. "I think he cares about Yang and Ruby, though. I mean… why else would he be here? He hasn't left their sides all week, even when Yang was throwing things at him."

Suspicious, Qrow glanced at Taiyang. "…I was under the impression you didn't like him."

"Oh, I don't," Taiyang admitted readily. "What father would? He's a teenage boy hanging around my teenage daughters. I don't trust him."

"That's… not what I meant." Qrow let out a groan. "Actually, to be honest, he reminds me of you at that age."

Taiyang blanched at that accusation, though he couldn't deny the comparison. "Given what I was like back then, that's only making it worse." A more serious expression settled onto his face. "I think he can reach Yang, though. In a way that you and I can't. So don't scare him off, Qrow. For her sake."

"…Weren't you cooking dinner?" Qrow pointed out.

Panic dawned on Taiyang's face. "Oh, Dust!" He disappeared, then reappeared a second later. "We're not finished with this discussion." Then he vanished once more.

Qrow settled into the old wooden chair next to Ruby's bed, staring at the slumbering face of his niece. She would wake up in her own time, he was sure. He wasn't worried about that.

He was far more concerned about what she would do after she awoke, and learned the fate of her school.

* * *

Another day, and Mercury was once more ready to start breaking things to relieve the tedium. Fighting the Grimm until he was bone tired has its advantages, but most of the ones in this area had been cleared out already. The ones that haunted Beacon were of too high a level to take on by himself, too. And he'd already performed maintenance on his legs a total of four times that afternoon. So he was a bit stuck for what to do.

He supposed he could always go argue with Yang some more, but her morose act wasn't particularly entertaining right now. Also, she'd thrown a lamp at his head that morning. Taiyang hadn't been particularly pleased about that.

But then, sitting here, watching a girl that had been asleep for almost a week, was definitely not on his list of things he found fun.

Why was he even here? He didn't owe Yang or Ruby anything. They'd been on opposite sides, after all. Villains versus heroes. If he just up and left, it wouldn't surprise anyone.

At the same time, he didn't really feel any compulsion to leave, either.

So he stayed.

Feeling something cold on his dangling hand, Mercury glanced down. A black and white corgi stared up at him, and barked once. "Hey, Zwei."

The dog barked again, and then ran off. After a moment, he barreled back in, something clenched in his jaws.

"That was fast. What's that you got there?" Mercury asked.

Zwei deposited the object into his hand.

"Oh, X-Ray and Vav!" Mercury exclaimed, sitting up straight. Now he wouldn't be quite so bored for a while. Though he had to wonder where the dog had procured the comic from. "Thanks."

Barking in acknowledgment, the canine sauntered off – his job complete.

Not for the first time, Mercury had to wonder if the dog was in fact a dog at all. What in Remnant was Zwei even made out of? Mercury vaguely recalled seeing one of the professors bat the creature and take down a goliath of a Beowulf.

Well, regardless, he now had something to keep his mind occupied for a bit. So there was that.

* * *

It was hours later that Taiyang found the teenager draped awkwardly in the chair, passed out with his legs dangling over one side, one arm laying across his stomach and the other trailing on the ground. Beside the boy's fingers lay a comic book, upended on the floor.

He snorted at the sight. Why didn't the kid just take the second bed in the corner?

Taiyang grabbed the comforter from the other bed and placed it over the boy. Mercury's face scrunched up at the action, a cold sweat beading on his brow.

The Hunter couldn't help but wonder was Mercury was dreaming about.


End file.
